From: Zhang Shurong zhang_shurong@foxmail.com
[ Upstream commit c30411266fd67ea3c02a05c157231654d5a3bdc9 ]
In anysee_master_xfer, msg is controlled by user. When msg[i].buf is null and msg[i].len is zero, former checks on msg[i].buf would be passed. Malicious data finally reach anysee_master_xfer. If accessing msg[i].buf[0] without sanity check, null ptr deref would happen. We add check on msg[i].len to prevent crash.
Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
Signed-off-by: Zhang Shurong zhang_shurong@foxmail.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl [hverkuil: add spaces around +] Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/usb/dvb-usb-v2/anysee.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/usb/dvb-usb-v2/anysee.c b/drivers/media/usb/dvb-usb-v2/anysee.c index aa45b5d263f6b..a1235d0cce92f 100644 --- a/drivers/media/usb/dvb-usb-v2/anysee.c +++ b/drivers/media/usb/dvb-usb-v2/anysee.c @@ -202,7 +202,7 @@ static int anysee_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
while (i < num) { if (num > i + 1 && (msg[i+1].flags & I2C_M_RD)) { - if (msg[i].len > 2 || msg[i+1].len > 60) { + if (msg[i].len != 2 || msg[i + 1].len > 60) { ret = -EOPNOTSUPP; break; }